build.go: Major rework, support Go modules

This commit is contained in:
Alexander Neumann 2018-08-30 20:53:42 +02:00
parent 71e0408390
commit 4734056583

289
build.go
View file

@ -1,3 +1,18 @@
// Description
//
// This program aims to make building Go programs for end users easier by just
// calling it with `go run`, without having to setup a GOPATH.
//
// For Go < 1.11, it'll create a new GOPATH in a temporary directory, then run
// `go build` on the package configured as Main in the Config struct.
//
// For Go >= 1.11 if the file go.mod is present, it'll use Go modules and not
// setup a GOPATH. It builds the package configured as Main in the Config
// struct with `go build -mod=vendor` to use the vendored dependencies.
// The variable GOPROXY is set to `off` so that no network calls are made. All
// files are copied to a temporary directory before `go build` is called within
// that directory.
// BSD 2-Clause License
//
// Copyright (c) 2016-2018, Alexander Neumann <alexander@bumpern.de>
@ -37,7 +52,6 @@ import (
"io/ioutil"
"os"
"os/exec"
"path"
"path/filepath"
"runtime"
"strconv"
@ -48,12 +62,9 @@ import (
var config = Config{
Name: "restic", // name of the program executable and directory
Namespace: "github.com/restic/restic", // subdir of GOPATH, e.g. "github.com/foo/bar"
Main: "github.com/restic/restic/cmd/restic", // package name for the main package
Main: "./cmd/restic", // package name for the main package
DefaultBuildTags: []string{"selfupdate"}, // specify build tags which are always used
Tests: []string{ // tests to run
"github.com/restic/restic/internal/...",
"github.com/restic/restic/cmd/...",
},
Tests: []string{"./..."}, // tests to run
MinVersion: GoVersion{Major: 1, Minor: 9, Patch: 0}, // minimum Go version supported
}
@ -73,41 +84,12 @@ var (
runTests bool
enableCGO bool
enablePIE bool
goVersion = ParseGoVersion(runtime.Version())
)
// specialDir returns true if the file begins with a special character ('.' or '_').
func specialDir(name string) bool {
if name == "." {
return false
}
base := filepath.Base(name)
if base == "vendor" || base[0] == '_' || base[0] == '.' {
return true
}
return false
}
// excludePath returns true if the file should not be copied to the new GOPATH.
func excludePath(name string) bool {
ext := path.Ext(name)
if ext == ".go" || ext == ".s" || ext == ".h" {
return false
}
parentDir := filepath.Base(filepath.Dir(name))
if parentDir == "testdata" {
return false
}
return true
}
// updateGopath builds a valid GOPATH at dst, with all Go files in src/ copied
// to dst/prefix/, so calling
// copy all Go files in src to dst, creating directories on the fly, so calling
//
// updateGopath("/tmp/gopath", "/home/u/restic", "github.com/restic/restic")
// copy("/tmp/gopath/src/github.com/restic/restic", "/home/u/restic")
//
// with "/home/u/restic" containing the file "foo.go" yields the following tree
// at "/tmp/gopath":
@ -118,21 +100,17 @@ func excludePath(name string) bool {
// └── restic
// └── restic
// └── foo.go
func updateGopath(dst, src, prefix string) error {
verbosePrintf("copy contents of %v to %v\n", src, filepath.Join(dst, prefix))
func copy(dst, src string) error {
verbosePrintf("copy contents of %v to %v\n", src, dst)
return filepath.Walk(src, func(name string, fi os.FileInfo, err error) error {
if name == src {
return err
}
if specialDir(name) {
if fi.IsDir() {
if name == ".git" {
return filepath.SkipDir
}
return nil
}
if err != nil {
return err
}
@ -141,17 +119,13 @@ func updateGopath(dst, src, prefix string) error {
return nil
}
if excludePath(name) {
return nil
}
intermediatePath, err := filepath.Rel(src, name)
if err != nil {
return err
}
fileSrc := filepath.Join(src, intermediatePath)
fileDst := filepath.Join(dst, "src", prefix, intermediatePath)
fileDst := filepath.Join(dst, intermediatePath)
return copyFile(fileDst, fileSrc)
})
@ -166,6 +140,15 @@ func directoryExists(dirname string) bool {
return stat.IsDir()
}
func fileExists(filename string) bool {
stat, err := os.Stat(filename)
if err != nil && os.IsNotExist(err) {
return false
}
return stat.Mode().IsRegular()
}
// copyFile creates dst from src, preserving file attributes and timestamps.
func copyFile(dst, src string) error {
fi, err := os.Stat(src)
@ -185,30 +168,34 @@ func copyFile(dst, src string) error {
fdst, err := os.Create(dst)
if err != nil {
_ = fsrc.Close()
return err
}
if _, err = io.Copy(fdst, fsrc); err != nil {
_, err = io.Copy(fdst, fsrc)
if err != nil {
_ = fsrc.Close()
_ = fdst.Close()
return err
}
if err == nil {
err = fsrc.Close()
}
if err == nil {
err = fdst.Close()
}
if err == nil {
err = os.Chmod(dst, fi.Mode())
}
if err == nil {
err = os.Chtimes(dst, fi.ModTime(), fi.ModTime())
}
if err != nil {
_ = fsrc.Close()
return err
}
err = fsrc.Close()
if err != nil {
return err
}
err = os.Chmod(dst, fi.Mode())
if err != nil {
return err
}
return os.Chtimes(dst, fi.ModTime(), fi.ModTime())
}
// die prints the message with fmt.Fprintf() to stderr and exits with an error
@ -224,7 +211,7 @@ func showUsage(output io.Writer) {
fmt.Fprintf(output, "OPTIONS:\n")
fmt.Fprintf(output, " -v --verbose output more messages\n")
fmt.Fprintf(output, " -t --tags specify additional build tags\n")
fmt.Fprintf(output, " -k --keep-gopath do not remove the GOPATH after build\n")
fmt.Fprintf(output, " -k --keep-tempdir do not remove the temporary directory after build\n")
fmt.Fprintf(output, " -T --test run tests\n")
fmt.Fprintf(output, " -o --output set output file name\n")
fmt.Fprintf(output, " --enable-cgo use CGO to link against libc\n")
@ -267,17 +254,17 @@ func cleanEnv() (env []string) {
}
// build runs "go build args..." with GOPATH set to gopath.
func build(cwd string, ver GoVersion, goos, goarch, goarm, gopath string, args ...string) error {
func build(cwd string, env map[string]string, args ...string) error {
a := []string{"build"}
if ver.AtLeast(GoVersion{1, 10, 0}) {
if goVersion.AtLeast(GoVersion{1, 10, 0}) {
verbosePrintf("Go version is at least 1.10, using new syntax for -gcflags\n")
// use new prefix
a = append(a, "-asmflags", fmt.Sprintf("all=-trimpath=%s", gopath))
a = append(a, "-gcflags", fmt.Sprintf("all=-trimpath=%s", gopath))
a = append(a, "-asmflags", fmt.Sprintf("all=-trimpath=%s", cwd))
a = append(a, "-gcflags", fmt.Sprintf("all=-trimpath=%s", cwd))
} else {
a = append(a, "-asmflags", fmt.Sprintf("-trimpath=%s", gopath))
a = append(a, "-gcflags", fmt.Sprintf("-trimpath=%s", gopath))
a = append(a, "-asmflags", fmt.Sprintf("-trimpath=%s", cwd))
a = append(a, "-gcflags", fmt.Sprintf("-trimpath=%s", cwd))
}
if enablePIE {
a = append(a, "-buildmode=pie")
@ -285,9 +272,9 @@ func build(cwd string, ver GoVersion, goos, goarch, goarm, gopath string, args .
a = append(a, args...)
cmd := exec.Command("go", a...)
cmd.Env = append(cleanEnv(), "GOPROXY=off", "GOPATH="+gopath, "GOARCH="+goarch, "GOOS="+goos)
if goarm != "" {
cmd.Env = append(cmd.Env, "GOARM="+goarm)
cmd.Env = append(cleanEnv(), "GOPROXY=off")
for k, v := range env {
cmd.Env = append(cmd.Env, k+"="+v)
}
if !enableCGO {
cmd.Env = append(cmd.Env, "CGO_ENABLED=0")
@ -296,20 +283,30 @@ func build(cwd string, ver GoVersion, goos, goarch, goarm, gopath string, args .
cmd.Dir = cwd
cmd.Stdout = os.Stdout
cmd.Stderr = os.Stderr
verbosePrintf("go %s\n", a)
verbosePrintf("chdir %q\n", cwd)
verbosePrintf("go %q\n", a)
return cmd.Run()
}
// test runs "go test args..." with GOPATH set to gopath.
func test(cwd, gopath string, args ...string) error {
args = append([]string{"test"}, args...)
func test(cwd string, env map[string]string, args ...string) error {
args = append([]string{"test", "-count", "1"}, args...)
cmd := exec.Command("go", args...)
cmd.Env = append(cleanEnv(), "GOPATH="+gopath)
cmd.Env = append(cleanEnv(), "GOPROXY=off")
for k, v := range env {
cmd.Env = append(cmd.Env, k+"="+v)
}
if !enableCGO {
cmd.Env = append(cmd.Env, "CGO_ENABLED=0")
}
cmd.Dir = cwd
cmd.Stdout = os.Stdout
cmd.Stderr = os.Stderr
verbosePrintf("go %s\n", args)
verbosePrintf("chdir %q\n", cwd)
verbosePrintf("go %q\n", args)
return cmd.Run()
}
@ -457,9 +454,8 @@ func (v GoVersion) String() string {
}
func main() {
ver := ParseGoVersion(runtime.Version())
if !ver.AtLeast(config.MinVersion) {
fmt.Fprintf(os.Stderr, "%s detected, this program requires at least %s\n", ver, config.MinVersion)
if !goVersion.AtLeast(config.MinVersion) {
fmt.Fprintf(os.Stderr, "%s detected, this program requires at least %s\n", goVersion, config.MinVersion)
os.Exit(1)
}
@ -468,11 +464,14 @@ func main() {
skipNext := false
params := os.Args[1:]
targetGOOS := runtime.GOOS
targetGOARCH := runtime.GOARCH
targetGOARM := ""
goEnv := map[string]string{}
buildEnv := map[string]string{
"GOOS": runtime.GOOS,
"GOARCH": runtime.GOARCH,
"GOARM": "",
}
gopath := ""
tempdir := ""
var outputFilename string
@ -498,7 +497,7 @@ func main() {
outputFilename = params[i+1]
case "--tempdir":
skipNext = true
gopath = params[i+1]
tempdir = params[i+1]
case "-T", "--test":
runTests = true
case "--enable-cgo":
@ -507,13 +506,13 @@ func main() {
enablePIE = true
case "--goos":
skipNext = true
targetGOOS = params[i+1]
buildEnv["GOOS"] = params[i+1]
case "--goarch":
skipNext = true
targetGOARCH = params[i+1]
buildEnv["GOARCH"] = params[i+1]
case "--goarm":
skipNext = true
targetGOARM = params[i+1]
buildEnv["GOARM"] = params[i+1]
case "-h":
showUsage(os.Stdout)
return
@ -524,7 +523,7 @@ func main() {
}
}
verbosePrintf("detected Go version %v\n", ver)
verbosePrintf("detected Go version %v\n", goVersion)
if len(buildTags) == 0 {
verbosePrintf("adding build-tag release\n")
@ -542,50 +541,16 @@ func main() {
die("Getwd(): %v\n", err)
}
if gopath == "" {
gopath, err = ioutil.TempDir("", fmt.Sprintf("%v-build-", config.Name))
if err != nil {
die("TempDir(): %v\n", err)
}
}
verbosePrintf("create GOPATH at %v\n", gopath)
if err = updateGopath(gopath, root, config.Namespace); err != nil {
die("copying files from %v/src to %v/src failed: %v\n", root, gopath, err)
}
vendor := filepath.Join(root, "vendor")
if directoryExists(vendor) {
if err = updateGopath(gopath, vendor, filepath.Join(config.Namespace, "vendor")); err != nil {
die("copying files from %v to %v failed: %v\n", root, gopath, err)
}
}
defer func() {
if !keepGopath {
verbosePrintf("remove %v\n", gopath)
if err = os.RemoveAll(gopath); err != nil {
die("remove GOPATH at %s failed: %v\n", gopath, err)
}
} else {
verbosePrintf("leaving temporary GOPATH at %v\n", gopath)
}
}()
if outputFilename == "" {
outputFilename = config.Name
if targetGOOS == "windows" {
if buildEnv["GOOS"] == "windows" {
outputFilename += ".exe"
}
}
cwd, err := os.Getwd()
if err != nil {
die("Getwd() returned %v\n", err)
}
output := outputFilename
if !filepath.IsAbs(output) {
output = filepath.Join(cwd, output)
output = filepath.Join(root, output)
}
version := getVersion()
@ -596,13 +561,65 @@ func main() {
ldflags := "-s -w " + constants.LDFlags()
verbosePrintf("ldflags: %s\n", ldflags)
args := []string{
"-tags", strings.Join(buildTags, " "),
"-ldflags", ldflags,
"-o", output, config.Main,
var (
buildArgs []string
testArgs []string
)
mainPackage := config.Main
if strings.HasPrefix(mainPackage, config.Namespace) {
mainPackage = strings.Replace(mainPackage, config.Namespace, "./", 1)
}
err = build(filepath.Join(gopath, "src"), ver, targetGOOS, targetGOARCH, targetGOARM, gopath, args...)
buildTarget := filepath.FromSlash(mainPackage)
buildCWD := ""
if goVersion.AtLeast(GoVersion{1, 11, 0}) && fileExists("go.mod") {
verbosePrintf("Go >= 1.11 and 'go.mod' found, building with modules\n")
buildCWD = root
buildArgs = append(buildArgs, "-mod=vendor")
testArgs = append(testArgs, "-mod=vendor")
} else {
if tempdir == "" {
tempdir, err = ioutil.TempDir("", fmt.Sprintf("%v-build-", config.Name))
if err != nil {
die("TempDir(): %v\n", err)
}
}
verbosePrintf("Go < 1.11 or 'go.mod' not found, create GOPATH at %v\n", tempdir)
targetdir := filepath.Join(tempdir, "src", filepath.FromSlash(config.Namespace))
if err = copy(targetdir, root); err != nil {
die("copying files from %v to %v/src failed: %v\n", root, tempdir, err)
}
defer func() {
if !keepGopath {
verbosePrintf("remove %v\n", tempdir)
if err = os.RemoveAll(tempdir); err != nil {
die("remove GOPATH at %s failed: %v\n", tempdir, err)
}
} else {
verbosePrintf("leaving temporary GOPATH at %v\n", tempdir)
}
}()
buildCWD = targetdir
goEnv["GOPATH"] = tempdir
buildEnv["GOPATH"] = tempdir
}
verbosePrintf("environment:\n go: %v\n build: %v\n", goEnv, buildEnv)
buildArgs = append(buildArgs,
"-tags", strings.Join(buildTags, " "),
"-ldflags", ldflags,
"-o", output, buildTarget,
)
err = build(buildCWD, buildEnv, buildArgs...)
if err != nil {
die("build failed: %v\n", err)
}
@ -610,7 +627,9 @@ func main() {
if runTests {
verbosePrintf("running tests\n")
err = test(filepath.Join(gopath, "src"), gopath, config.Tests...)
testArgs = append(testArgs, config.Tests...)
err = test(buildCWD, goEnv, testArgs...)
if err != nil {
die("running tests failed: %v\n", err)
}